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3 years ago

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Without using a calculator, determine the number of real zeros of the function

1 answer:

Natalija [7]3 years ago

4 0

Answer:

1, -6

Step-by-step explanation:

Since there are alike numbers, add them together.

4x+x= 5x

Now the function is: f(x)= $x^{2}$ +5x-6

The function is in $a^{2}$ +bx+c form.

So find the factors of a x c = b.

Factors of -6(a) that fits (b)5 is (-1,6).

Then you just factor it:

f(x)= $x^{2}$ +5x-6

(x-1)(x+6)

x-1= 0 x+6=0

+1 +1 -6 -6

x=1 x=-6

Those are the real zeroes: 1, -6

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3 years ago

How do i solve using the substitution method?<br> x+y=-1 <br> y=-2x

leonid [27]

Answer:

$(1, -2)$

Step-by-step explanation:

<u>Step 1: Set the second equation into the first </u>

$x + (-2x) = -1$

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$-x / -1 = -1 / -1$

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<u>Step 2: Solve the second equation </u>

$y = -2(1)$

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3 years ago

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After the drama club sold 100 tickets to a show, it had $300 in profit. After the next show, it had sold a total of 200 tickets

Alinara [238K]

Answer:

Option a : $y-300 = 4(x - 100)$

Step-by-step explanation:

Given :

The drama club sold 100 tickets to a show, it had $300 in profit.

The next show, it had sold a total of 200 tickets and had a total of $700 profit.

To Find : Equation models the total profit, y, based on the number of tickets sold, x

Solution :

For 100 tickets he had $300 in profit .

⇒ ( $x_{1} ,y_{1}$ )=(100,300)

For 200 tickets he had $700 in profit .

⇒ ( $x_{2} ,y_{2}$ )=(200,700)

We will use point slope form i.e.

$y-y_{1} = m(x - x_{1})$ --(A)

Now, to calculate m we will use slope formula :

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$m = \frac{700 -300}{200-100}$

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